It's always Pattern Damage and with Heart's Blood has never been Bashing damage
The rote does not do bashing damage and never did, it has always done damage to the underlying pattern and always had special rules for when that damage would go away. In short, it can't be healed by magic and it is damage to the underlying pattern. Depending on the edition, it was pointed out more or less that it takes healing like any lethal or aggravated damage, like any normal mortal.
Since pattern damage is healing like any non-bashing damage, the time to recuperate the bruised level is not an hour, it's a whole day of rest and recuperation, but with the caveat that you can't speed it along with magic in any way.
Further, all the Quintessence created is instantly used to fuel an other, urgent "Now or never" spell and is pretty much how some martyrs burnt out their lives to achieve a miracle.
Edition Versions
M20
Heart’s Blood
Self-sacrifice allows a mage to use Prime 1 in order to
draw upon his personal life-force; by cutting himself, pushing
the limits of his endurance, working himself to exhaustion,
or otherwise inflicting damage upon himself in order to draw
upon his life-force, that character can “give till it hurts.” Each
success on the Arete roll moves one point of Quintessence from
the mage’s Pattern into the task at hand, lowering his difficulty
at that task by -1 per point. (At the Storyteller’s discretion, this
feat might allow the player to bend the usual -3 modifier limit;
the usual limits on magick-roll difficulties, however, still apply.)
In game terms, a mage has 10 points of Quintessence in
addition to that character’s Avatar Background and/ or his
current Quintessence rating. Each of those Quintessence points
translates to one health level, with the last three taking that
mage below Incapacitated. If he uses those points, then he dies.
Damage inflicted by “heart’s blood” self-sacrifice can be
healed only by time and rest, not by magick. And so, you probably
won’t want to go beyond the Bruised level unless your mage is
desperate enough to do whatever must be done.
Mage the Ascension: How do you do that, 20th Anniversary Edition, p.50.
Bashing Damage certainly exists (page 334, 406, 412), but, whenever bashing damage is called for, it's explicitly notioned as such. Such as the callout "#2 = Bashing damage, not lethal." in the Explosives chart (page 455). In regards to magic, it's explicitly called out on page 504: Mind the only sphere that even is able to inflict bashing damage, all other spheres do lethal, unless it's Time or Correspondence alone (who can't do damage at all singly), and Entropy (which can't do damage below 4 on its own, and at 4 does aggravated on its own).
So yes, the standard rules dictate lethal damage to the pattern here, because Prime is not Mind and does, on its own, lethal damage.
Revised
• Heart’s Blood — An initiate of Prime can easily sense
the flow of Quintessence through his own body — his life energy.
This energy flows from the Tellurian, through the Life Pattern
and back out to rejoin the cosmos. Each point corresponds to a
health level, the last three on beyond Incapacitated and their
loss resulting in death.
In desperate times, mages skilled in Prime — typically
the Celestial Chorus and the Verbena — can push themselves
beyond their limits and “give ’til it hurts,” taking the additional
health levels as points of Quintessence above and beyond what
is stored in their Avatars. Such damage may only be healed by
time and bed rest, not magic, so most mages will usually only risk
the Bruised health level. Mages of the Chorus, however, have
burned themselves out in acts of martyrdom to perform one last
holy miracle, while Verbena with low Avatar ratings often use
their Bruised health level as a power reservoir, considering the
sacrifice of heart’s blood more holy than the spiritual energy
used by most mages.
Mage the Ascension, Revised Edition, p.182.
Mage Revised does know Bashing damage, but page 151 specifies that all magic effects do lethal damage unless specified otherwise. That list only goes Mind (Bashing only), Entropy below 4 (no damage) and Forces getting one Bonus damage. The Chart on 209 specifies likewise:
Scoring Damage: Each success expended to score damage
inflicts up to two levels of damage. For Mind attacks, this damage is bashing; for most other Spheres, it’s lethal. Charged with
Quintessence, it’s aggravated. Forces attacks inflict one extra
level of damage automatically.
Mage the Ascension, Revised Edition, p.209.
As such, lethal damage to the pattern it is, because it is not a mind effect, and Prime inflicts at least lethal damage.
Sorcerer's Crusade
Heart's Blood (• Prime)
In desperate straits, a sorcerer can reach into his very
Essence and pull Quintessence from his soul. By praying to
whatever God or gods he follows, the mystick concentrates
his inner reserves into much-needed power. As that power
flows outward, so too does his life. A true martyr can
literally burn himself away from within while performing a
final miracle. While miracle-workers and Pagans are notorious for this sort of sacrifice, any magus — even a Daedalean
— with the right Arts can perform it.
[In game terms, each magus has 10 points of Quintessence above and beyond his Daemon rating and/ or
Quintessence score. Each one of these points translates to
a Health Level; the last three take the magus below Incapacitated. If he uses these points, he dies.
[Through this weavery, the magician can lap those
reserves. A successful Arete roll drains Quintessence points.
— and Health Levels — according the Damage and Duration chart. Each Health Level equals one point of
Quintessence. This self-inflicted damage cannot be healed
magickally — only normal rest and recovery can restore the
lost life force. Once channeled, the Quintessence may be
used normally. This spell does not allow a magus to tap
another being's reserves, only his own.]
Mage: the Sorcerer's Crusade, p.269.
There is no "Bashing Damage" in Sorcerer's Crusade. The Chapter on Damage is called "Mortality", starts at page 206, and explains that there is Damage marked with "checks", there's Aggravated damage demarked with X, and optionally there's a stunning effect of receiving damage. So, "normal" damage it is, which is what later revisions call lethal after bashing damage was added.
2nd Edition
• Heart's Blood - A Disciple of Prime can sense the flow of
Quintessence - his life energy - through his own body. As
vampires well know, each human has about 10 points of this upon
which they may feed. Each point corresponds to a Health Level.
The last three go beyond Incapacitated; losing them will kill him.
In desperate times, mages skilled in Prime can push them·
selves beyond their limits and "give till it hurts," taking the
additional Health Levels as points of Quintessence above and
beyond what is stored in their Avarars. Such damage may only he
healed by time and bed rest, not magick (see "Better Body"), so
most mages will usually only risk the first "Bruised" Health Level.
Mages of the Chorus, however, have martyred themselves to
perform one last holy miracle, while Verbena with low Avatar
racings often consider the sacrifice of heart's blood more holy than
the spiritual energy used by most mages.
Mage the Ascension, 2nd Edition, p.214.
As Page 170/171 tells, only those damages listed as Aggravated on 171 are, all others are "normal" damage. There is no Bashing damage in 2nd Edition Mage, in fact, the whole health track does not differentiate any Damage other than Aggravated Damage. Neither the introduction to Health (page 137) nor the Injury Chapter (page 264) do tell you that anything like Bashing damage even exists. There's only Normal (/) and Aggravated Damage (X). Note that this means there is no * of later editions or other games!
1st Edition
Mage the Ascension, 1st Edition, p.210, does not list this classic but instead, a way to cram Quint into your pattern, not convert your life force to Quintessence. Book of Shadows - the dedicated player's guide - does not have it either, Book of Chantries does not deliver on the topic of magic effects at all, and Book of Mirrors as the Storyteller Guide does neither. So far, I could not locate a source that proves that this effect existed in 1st Edition or before 1997.
Origin of problem
The problem is the very shoddily edited 3rd party Enlightened Grimoire by Charles Siegel. The book has correct pointers to rotes, but the summaries are wrong. For example, it writes the totally inappropriate summary claiming bashing damage where all quotes above clearly state that it is pattern damage.
It also seems to comingle the Heart's Blood with the similar "Self Sacrifice" from Verbena Revised, which is distinctly different - and more powerful - and also makes clear that it is pattern damage.
Note that this rote is absent in the Traditionbook Verbena from 1st Edition, and even in the revised edition it did conflict with the core book's Heart's Blood.
This different Rote could source a whole 14 Quintessence without killing you: Going for 14 points of Quintessence from your pattern by taking 7 lethal damage puts you in a coma for months, while Heart's Blood only gives you 7 points if you put yourself in that coma - and taking the 8th to 10th automatically kills you.
Self Sacrifice (Prime •)
The Norse god Odin hung himself from the branches
of the World Tree to gain knowledge of the runes. So
must the Verbena sometimes sacrifice for their magic.
Rituals of pain and endurance — as simple as cutting
runes into flesh or scourging or as complex as hanging
in imitation of Odin’s sacrifice or the Native American
Sun Dance — fuel Verbena magic. Other mages consider
such primitive and painful rituals unnecessary, but the
Verbena understand that sometimes pain is the best
way to know that you are alive, and the willingness to
sacrifice is one of the greatest strengths.
System: For each level of bashing damage that she
suffers, the mage gains a point of Quintessence she can
use for a particular spell. For each level of lethal damage,
the mage gains an additional point of Quintessence.
This damage is done directly to the mage’s Pattern, so
it cannot be healed using magic, only time and rest. In
essence, the Verbena is drawing upon her own life force,
breaking down the Quintessence of her own being, to
fuel her magic.
MET: Apprentice Prime. Each health level of bashing damage suffered adds a Quintessence Trait that can
only be used for a single rote named when this rote is
cast. Lethal health levels add Quintessence Traits at the
same rate, but they can be used for any rote. No form
of magical healing can repair damage done by this rote,
only natural rest. Grades of Success: No effect.
Dark Ages: Old Faith mages cast this spell using
Autumn •, while the Valdaermen cast it using Galdrar •.
Verbena, Revised Edition, p.67.